The invention relates to a detachable cryogenic refrigerator expander.
Systems operating at cryogenic temperatures generally have a cryogenic refrigeration unit attached to the system to minimize or eliminate boil-off of the cryogenic coolant. A cryogenic refrigeration unit including an expansion device, compressor, and heat exchanger is known. High pressure fluid from the compressor is passed through the heat exchanger and introduced into the expansion device. Expansion of the fluid in the expansion device reduces the temperature and pressure of the fluid. Heat energy is transferred from the expanding fluid by the performance of mechanical work.
When the expansion device must be removed, either for maintenance or replacement, the cryogenic system is typically exposed to warmer temperatures and potential contaminates. Maintenance of the unit generally requires that the cryogenic system be shut down for at least a day.